The invention relates to an open-end spinning machine of the type having a stationary rotor housing which mounts a rotating rotor cup and a sliver opening unit which includes an opening roller assembly.
In connection with open-end spinning machines e.g. of rotor spinning machines, different embodiments of opening rollers are known.
In DE 35 43 428 A1, for example, an opening roller is described which comprises a bearing shaft at its rear side and is mounted with this bearing shaft in the bearing bracket of an opening roller housing. The bearing shaft has on its end a so-called drive whorl which is driven by a tangential belt having the same length as the machine and which is connected via a shaft to the base plate of the opening roller. On the opening roller's base plate mounted in such a manner that it can rotate, a so-called trimming ring is fixed in such a manner that it can be replaced. To replace the trimming ring the opening roller can be pivoted away from the tangential belt and subsequently dismounted from the opening roller housing at the front.
Furthermore, for example, opening rollers which are driven by a single motor are also known from DE 40 36 017 A1 or DE 100 54 697 A1. Such opening roller drives are formed as external rotors which are fixed by their stator to the opening roller housing and connected via the electric lines to the power supply of the textile machine. On this external rotor a trimming ring is also disposed in such a manner that it can be replaced.
However, it is disadvantageous in the case of these opening rollers driven by a single motor that to replace the trimming ring the drive of the opening roller must also be dismounted and in so doing electric lines or corresponding plug-in connectors must be disconnected. On re-mounting of the opening roller these plug-in connectors must then be carefully connected once again. The mounting and dismounting of opening rollers of this type thus prove to be relatively complicated and time-consuming.
Finally, in DE 196 50 597 and corresponding U.S. Pat. No. 5,850,730 an open-end spinning device is described whose opening roller with its bearing shaft is mounted in the bearing bracket of an opening roller housing and comprises a single drive formed as an external rotor. On the end of the bearing shaft of this opening roller a whorl is disposed which can be acted on by a brake element. The known opening roller is fixed in the bearing bracket by a spring wire which engages in an annular groove of the bearing shaft. Furthermore, a locking and unlocking device is present which can be actuated by a toggle switch disposed in front of the opening roller housing, said toggle switch being connected via a shaft to connecting links toward the rear. That is, by means of the toggle switch, connecting links which comprise different switching surfaces can be turned so that the brake is pressed onto the whorl and at the same time the power supply of the opening roller drive is interrupted. In an additional switching position the arresting of the bearing shaft of the opening roller in the bearing bracket can be discontinued and the brake once again released.
Also in the case of this known opening roller, as described above, in dismounting and mounting of the opening roller plug-in contacts must first be disconnected in a laborious and time-consuming manner and later connected once again.
Proceeding from the aforementioned state of the art, the objective of the invention is to provide an opening roller which is driven by a single motor but, e.g. for replacing a trimming ring, can be mounted and dismounted from its bearing bracket on the opening roller housing securely and without difficulty.